An envelope tracking method and device are provided. The envelope tracking method includes: acquiring, by a boost circuit, a target envelope tracking input current signal, and transmitting, by the boost circuit, the target envelope tracking input current signal to an amplifier circuit, where the amplifier circuit includes an operational amplifier and a feedback network, and the operational amplifier operates in a mode of floating ground; and performing, by the amplifier circuit, closed-loop conversion and amplification on the target envelope tracking input current signal and outputting, by the amplifier circuit, an envelope tracking output voltage.

An amplifier that amplifies a differential signal includes first and second input terminals for receiving two input signals; first and second diodes each including an anode and a cathode, the anodes being electrically connected to the first and second input terminals; first and second bias current sources being respectively electrically connected to the cathodes of the first and second diodes; an operational amplifier connected to the cathode of the first diode and the cathode of the second diode and configured to amplify a differential signal between signals generated at the cathodes of the first and second diodes; a capacitive element being electrically connected between an input and an output of the operational amplifier; and a differential amplifier provided between the operational amplifier and the first and second input terminals and configured to amplify the two input signals. The first and second bias current sources include a current mirror circuit.

An amplifier that amplifies a differential signal includes first and second input terminals for receiving two input signals; first and second diodes each including anode and cathode, the anodes being electrically connected to the first and second input terminals; first and second bias current sources being respectively electrically connected to the cathodes of the first and second diodes; an operational amplifier connected to the cathode of the first diode and the cathode of the second diode and configured to amplify a differential signal between signals generated at the cathodes of the first and second diodes; a capacitive element being electrically connected between an input and an output of the operational amplifier; and a differential amplifier provided between the operational amplifier and the first and second input terminals and configured to amplify the two input signals. The first and second bias current sources include a current mirror circuit.

An envelope tracking method and device are provided. The envelope tracking method includes: acquiring, by a boost circuit, a target envelope tracking input current signal, and transmitting, by the boost circuit, the target envelope tracking input current signal to an amplifier circuit, where the amplifier circuit includes an operational amplifier and a feedback network, and the operational amplifier operates in a mode of floating ground; and performing, by the amplifier circuit, closed-loop conversion and amplification on the target envelope tracking input current signal and outputting, by the amplifier circuit, an envelope tracking output voltage.